<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><br></div><div><br></div><div>Here’s the program:</div><div><div><font face="Courier New">#lang typed/racket</font></div><div><font face="Courier New"><br></font></div><div><font face="Courier New">(require plot/typed plot/typed/utils)</font></div><div><font face="Courier New"><br></font></div><div><font face="Courier New">(: vsum ((Listof (Vectorof Real)) -> (Vectorof Real)))</font></div><div><font face="Courier New">(define (vsum vs)</font></div><div><font face="Courier New"> (apply vector-map + vs))</font></div></div><div><br></div><div>It’s giving me this error:</div><div><div><font face="Courier New">. Type Checker: Bad arguments to polymorphic function in apply:</font></div><div><font face="Courier New">Domain: (a b ... b -> c) (Vectorof a) (Vectorof b) ... b</font></div><div><font face="Courier New">Arguments: (case-> (-> Zero) (Zero Zero -> Zero) (One Zero -> One) (Zero One -> One) (Positive-Byte Zero -> Positive-Byte) (Zero Positive-Byte -> Positive-Byte) (Byte Zero -> Byte) (Zero Byte -> Byte) (Positive-Index Zero -> Positive-Index) (Zero Positive-Index -> Positive-Index) (Index Zero -> Index) (Zero Index -> Index) (Positive-Fixnum Zero -> Positive-Fixnum) (Zero Positive-Fixnum -> Positive-Fixnum) (Nonnegative-Fixnum Zero -> Nonnegative-Fixnum) (Zero Nonnegative-Fixnum -> Nonnegative-Fixnum) (Negative-Fixnum Zero -> Negative-Fixnum) (Zero Negative-Fixnum -> Negative-Fixnum) (Nonpositive-Fixnum Zero -> Nonpositive-Fixnum) (Zero Nonpositive-Fixnum -> Nonpositive-Fixnum) (Fixnum Zero -> Fixnum) (Zero Fixnum -> Fixnum) (Positive-Byte Positive-Byte -> Positive-Index) (Byte Byte -> Index) (Positive-Byte Positive-Byte Positive-Byte -> Positive-Index) (Byte Byte Byte -> Index) (Positive-Index Index -> Positive-Fixnum) (Index Positive-Index -> Positive-Fixnum) (Positive-Index Index Index -> Positive-Fixnum) (Index Positive-Index Index -> Positive-Fixnum) (Index Index Positive-Index -> Positive-Fixnum) (Index Index -> Nonnegative-Fixnum) (Index Index Inde in: (apply vector-map + vs)</font></div></div><div><br></div><div><br></div></body></html>